Health monitoring devices, such as fitness and wellness devices, are capable of measuring a variety of physiological parameters and waveforms non-invasively via optical sensing. Light is applied to a measurement site, such as a user's wrist, finger, and ear, and the light is absorbed and scattered throughout the skin. An optical sensor in the health monitoring device captures the light that is reflected from or transmitted through the skin. The optical sensor, however, is subject to interferences caused by fluorescent bulbs, sun light, the electricity grid or network, and motion artifacts that are caused by the relative motion between the optical sensor and the user's measurement site. Thus, the light collected by the light sensor contains a component from the measurement site and component from one or more interferences. To estimate the physiological parameter and waveform, the optical sensor coverts the collected light into electrical signals, and the signal that represents the interference component is typically subtracted from the signal representing the measurement site component. After subtraction, only the component from the measurement site should remain, which is the component that is used to estimate the physiological parameter. However, subtraction cannot be performed instantaneously. A time delay exists between sampling the light and subtracting the interference component. The time delay can result in the creation of aliases in the signal, and the aliases produce errors in the estimation of the physiological parameter.